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Nutrient Data Resources

Monitoring Surface Water Chemistry (Temporally Integrated Monitoring of Ecosystems and Long Term Monitoring)

Surface water chemistry is a direct indicator of the potential effects of acidic deposition and the overall health of aquatic ecosystems. Two EPA administered monitoring programs provide information to assess the response of acid-sensitive watersheds most impacted by acidic deposition: the Temporally Integrated Monitoring of Ecosystems (TIME) project and the Long-Term Monitoring (LTM) project.

EPA Nitrogen Oxide Emission Monitoring

EPA Nitrogen Oxide Emission Monitoring is a long-term dataset of monitored nitrogen oxide emissions from power plants. Data are collected as part of EPA’s emissions trading programs.

National Atmospheric Deposition Program (NADP)

NADP Exitis a national, long term program that monitors nitrogen and other pollution in precipitation. The program is a cooperative effort between many different group, including EPA and other federal agencies, state, tribal and local governmental agencies, educational institutions, private companies, and non-governmental agencies. Established in 1977 to measure atmospheric deposition its effects on the environment, NADP serves as a complement to CASTNET. It consists of five sub-networks, including the National Trends Network which measures precipitation chemistry at more than 250 sites throughout North America, and the Ammonia Monitoring Network, which is the only network providing a consistent, long-term record of ammonia gas concentrations across the United States.

The Environmental Monitoring and Assessment Program (EMAP) Search EPA Archive

EMAP was a research program run by EPA's Office of Research and Development to develop the tools necessary to monitor and assess the status and trends of national ecological resources.

Environmental Monitoring and Assessment Program Data Search EPA Archive

The Environmental Monitoring and Assessment Program Data provides a list of links to EMAP and other environmental monitoring and assessment data websites.